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Once the endometrium has shed, which means that menstruation has taken place, the rest of the cycle is full of life-making.
There are 2 official phases of the menstrual cycle; the Follicular Phase and the Luteal Phase. I would say there are actually 5 phases to the menstrual cycle since each has its own importance.
Phase 1: Menstruation
The first phase of the menstrual cycle is menstruation. You could look at it as the last phase, but it is the only way to track the length of a cycle by counting when bleeding starts. Many women confuse the menstrual cycle with menstruation. If you ask women, “How long is your cycle?” Many will tell you about 4–7 days. We know that is not how long their cycle is, but they think we are talking about the menstruation part only.
From day one of bleeding to the next day one of bleeding, it is a menstrual cycle. So I would call menstruation, the bleeding, Aunt Flo, a friend, or whatever else you call it, the first of 5 phases of the menstrual cycle.
Phase 2: Let’s Start with the Hypothalamus
The hypothalamus (a gland in the brain) sends a chemical signal, FSH-RF Follicle Stimulating Hormone Releasing Factor, telling the another gland in the brain called the pituitary to secrete FSH – Follicle Stimulating Hormone and LH – Luteinizing (commonly misspelled luteinizing) Hormone into the blood, and together they work to mature follicles.
In order to understand all this, just stick to the initials and not the long terms.
FSH works its magic for around 7 days, with it starting to secrete towards the end of menstruation. As these follicles mature and ripen, they release estrogen. More growth, more estrogen oozes out, in a sense, into the bloodstream. This estrogen has many wonderful jobs, including thickening the uterine lining with blood in preparation for life and changing the alkalinity of the cervical mucus. The higher the estrogen in the blood, the better the egg-white cervical mucus. These changes affect the sex of the baby or even the ability of the sperm to survive.
Phase 3: Next up is Luteinizing Hormone
When there is enough estrogen in the bloodstream the hypothalamus is signaled again, and it releases Luteinizing Hormone Releasing Factor LH-RF, which again signals the pituitary to create a surge of LH. This surge is what triggers the follicle of the month (the most mature) to burst, and out comes an egg.
Phase 4: Introducing Ovulation
Ovulation is often recognized by sensitive women as twinges in the ovary area, called Mittelschmerz, more commonly by monitoring basal body temperature (around .3-.5 degrees rise on average with a second rise after fertilization) or with the Fertility Tracker, tracking ferning patterns.
At the place where the egg was released from the follicle, another amazing thing is now happening. The follicle that is left behind becomes what is called the Corpus Luteum (yellow body), and it begins to heal. As it does, the hormones estrogen and, mostly, progesterone are produced. If pregnancy does not occur, the corpus luteum will become the corpus albicans (white body).
The ovary is signaled to contract so that the egg can travel more efficiently down the fallopian tube by way of tiny hairlike structures called cilia. The egg is not fertilized in the uterus, as some believe. Sperm and egg meet in these tubes and make their way happily down to the uterus, where they will settle into the uterine lining and make a home.
Progesterone is signaled to increase (it is now the dominant hormone), and mucus is produced to cover the blood-filled uterus (from the effects of estrogen). This is a protective mucus that provides nutrition and also fluffs up the lining in anticipation of life to nest upon. If pregnancy does not occur, then the blood flow to the surface ceases and the lining will prepare to shed. Since progesterone is no longer being produced at this time, estrogen becomes the dominant hormone.
Phase 5: BABY!
If your sperm and egg have connected within the 24-48-hour window of time when the egg is viable, they have begun to meld into your beautiful baby boy or girl. You are pregnant! Life is NOW! The Corpus Luteum will continue to make progesterone up until the 6–9th month. The estrogen and progesterone at this point, among other things, are responsible for the growth of the placenta which will take over the nourishment of the baby between 8–12 weeks. Your baby will have a heartbeat in a matter of days, and you will soon know you are pregnant through a missed period or other signs. You can read more about those in our list of articles on Early Pregnancy Signs and Symptoms.
So that is the dance of the hormones and the beginning of your understanding of the phases of the menstrual cycle.